JP5249631B2 - Synthetic faux leather skin layer coating - Google Patents

Description

The present invention relates to a skin layer-forming paint of synthetic imitation leather, and more particularly, skin layer and the adhesive layer can be formed without the use of organic solvents synthesis Artificial leather skin layer forming paint about the.

  Polyurethane resins have excellent physical properties such as wear resistance, flexibility, flexibility, flexibility, processability, adhesion, and chemical resistance, as well as excellent suitability for various processing methods. Polyurethane resin that is widely used as a binder for materials for materials (artificial leather and synthetic leather), various coating agents, inks, paints, etc., or as a material for films, sheets and various molded products. Has been proposed. Here, the polyurethane-based resin is a general term for a polyurethane resin, a polyurea resin, and a polyurethane-polyurea resin.

  These polyurethane resins are basically obtained by reacting a high molecular weight polyol, an organic polyisocyanate, and, if necessary, a chain extender, and have various performances depending on the types and combinations of these components. A polyurethane-based resin is provided.

  In particular, synthetic artificial leather using a polyurethane resin can obtain a texture close to that of natural leather, and is therefore often used in fields that require a high-class feeling such as clothing use, furniture, and vehicle interior materials. In recent years, in addition to the above, from the viewpoint of environmental protection, there is a strong demand for the development of a synthetic artificial leather system that takes ecology into consideration.

  Conventionally, synthetic artificial leather using a polyurethane-based resin has been produced by, for example, a wet method that undergoes the following main processes. First, for example, a solution of an organic solvent mainly composed of N, N-dimethylformamide (DMF), which is a polyurethane resin, is applied on a fibrous base material layer and solidified in water to form a microporous layer.

  Next, a polyurethane resin solution dissolved in various organic solvents is directly coated on the microporous layer with a coating machine such as a gravure and dried to form a skin layer (silver surface layer), or a polyurethane resin. Examples include a method in which an adhesive layer is formed on a film surface formed by applying a solution on a release paper and dried to transfer these layers to the microporous layer (Non-patent Document 1, Patent Document 1, 2).

  As described above, most of polyurethane-based resins for producing synthetic artificial leather are used as solutions dissolved in various organic solvents. Therefore, in the drying process, the organic solvent is released into the atmosphere. From the viewpoint of environmental problems (VOC countermeasures), safety and health, and fire fighting countermeasures, there is an increasing need for polyurethane resin aqueous dispersions that do not use organic solvents. ing.

  Conventional coatings made of polyurethane resin aqueous dispersions are used as materials for automobiles and furniture that require durability. Adhesion with substrates, flexibility and water resistance, especially against human sebum The required performance of synthetic artificial leather such as oil resistance, wear resistance, and durability (weather resistance, hydrolysis resistance, heat resistance, etc.) is not fully satisfied, and improvements are required.

Edited by Keiji Iwata, Polyurethane resin handbook, pages 571-599, 15. Polyurethane leather (published by Nikkan Kogyo Shimbun, September 25, 1987) JP-A-5-5280 JP-A-9-31861

  However, polyurethane-based resins used for synthetic artificial leather (artificial leather, synthetic leather) and various coating agents are usually solvent-based polyurethane resins that are usually used as organic solvent solutions. The current situation is that work environment is not supported. In addition, the physical properties required for polyurethane resins in the above applications include hydrolysis resistance, light resistance, heat resistance, gas discoloration resistance, wrinkle resistance, and oleic acid resistance (human sweat component) as durability. In particular, the physical properties required for synthetic artificial leather include natural leather-like appearance, soft texture, high strength, wear resistance, low temperature flexibility, surface touch, blocking resistance and adhesion to substrates. Etc.

Although the synthetic artificial leather has excellent characteristics unique to each material suitable for automobile interior materials and furniture materials, it has several problems and does not satisfy all the functions described above. In addition, there is a demand for synthetic artificial leather that is more functional than conventional ones and that is suitable for automobile interior materials and furniture materials.
Accordingly, an object of the present invention is to provide a coating material for forming a skin layer of a synthetic artificial leather and a method for producing the synthetic artificial leather that solve the above-mentioned conventional problems.

The above object is achieved by the present invention described below. That is, the present invention contains a siloxane-modified urethane resin (1) and an aqueous crosslinking agent (2) in an aqueous medium, and the siloxane-modified urethane resin (1) has at least one active in the molecule. Compound (a) having a hydrogen-containing group and a hydrophilic group other than a hydroxyl group, polysiloxane (b) having at least one active hydrogen-containing group, polyol and / or polyamine (c), and polyisocyanate (d ), The polyol and / or polyamine (c) is a polycarbonate diol, the aqueous crosslinking agent (2) is an oxazoline crosslinking agent, and the compounds (a) to ( The amount of c) used is such that the compound (a) is 0.01 to 30% by mass, the compound (b) is 1 to 20% by mass, and the total amount of the compounds (a) to (c) is The compound (d) has an equivalent ratio (OH / NCO) of the total active hydrogen-containing groups of the compounds (a) to (c) and the isocyanate groups of the compound (d) of 0.9 mass%. Provided is a coating material for forming a skin layer of synthetic artificial leather (hereinafter sometimes simply referred to as “paint”), characterized in that the usage amount is set to ˜1.1.

In the present invention, the ratio of the polysiloxane segment in the siloxane-modified urethane resin (1) is 1 to 20 % by mass, and the number average molecular weight of the resin is 2,000 to 500,000. Dearuko and; the aqueous crosslinking agent (2), Tg is -5~90 (℃), it is preferable oxazoline group equivalent of oxazoline crosslinking agents 100-400.

  As a result of intensive studies to solve the above problems, the present inventors have found that the coating film of the present invention has a urethane resin modified with siloxane and crosslinked with a crosslinking agent. Compared with a coating made of siloxane, it has the slipperiness that is characteristic of siloxane, and wear resistance is remarkably improved. In addition, flexibility and contamination at low temperatures are improved, and weather resistance is achieved by a crosslinking effect. Durability such as heat resistance is improved. By using such a coating material of the present invention, the design and soft touch properties are good, and the mechanical strength, flex resistance, slipping property, hydrolysis resistance, weather resistance, heat resistance, low temperature characteristics, It was found that a synthetic artificial leather excellent in solvent resistance, chemical resistance, heat insulation and oleic acid resistance (human sebum component) can be obtained.

  In addition to the above matters, in the present invention, the skin layer and the adhesive layer (or microporous layer) are formed by using a paint that does not contain an organic solvent, so that a volatile organic solvent (VOC) such as an organic solvent can be used. Emissions can be reduced.

  Next, the present invention will be described in more detail by giving the best mode for carrying out the invention. The siloxane-modified urethane resin used in the present invention (hereinafter sometimes simply referred to as “the resin of the present invention”) is a compound having at least one active hydrogen-containing group and a hydrophilic group other than a hydroxyl group in the molecule (hereinafter referred to as “the resin of the present invention”). (Sometimes simply referred to as “compound a”) (hydrophilic groups other than hydroxyl groups include, for example, completely or partially neutralized carboxyl groups or sulfonic acid groups, fully or partially neutralized primary groups, and the like. A tertiary amino group), a polysiloxane having at least one active hydrogen-containing group (hereinafter simply referred to as “compound b”), a polyol and / or a polyamine (hereinafter simply referred to as “compound c”). And a polyisocyanate (hereinafter sometimes simply referred to as “compound d”).

  In the above, the compound a to c are used in an amount of 0.01 to 30% by mass, preferably 1 to 15% by mass of compound a, 0.1 to 50% by mass, preferably 1 to 20% by mass of compound b. c is 10 to 95% by mass, preferably 20 to 70% by mass, and the compound d has an equivalent ratio (OH / NCO) of the total active hydrogen-containing groups of the compounds a to c and the isocyanate groups of the compound d. The amount used is 0.9 to 1.1, preferably 1.0. In addition, the said compounds ac are used in the ratio which the total amount of compound ac is 100 mass% within the said range.

  In the resin of this invention, it is preferable that content of the segment which consists of the said compound a is 0.1-30 mass%. More preferably, it is 1-15 mass%. When the content is less than 0.1% by mass, it is insufficient in terms of the emulsion stability of the resin and the adhesion to the substrate, and when the content exceeds 30% by mass, the water resistance of the resin is insufficient. Causes a decrease. Moreover, it is preferable that content of the polysiloxane segment which consists of the said compound b is 0.1-50 mass%. More preferably, it is 1-20 mass%. When the content is less than 0.1% by mass, it is insufficient in terms of resin slipperiness and blocking resistance. On the other hand, when the content exceeds 50% by mass, it is based on a resin base material (such as TPO). It may cause poor adhesion and contamination due to migration of siloxane components.

  In addition, content of the said segment of a-c is used in the ratio which the total amount of compound ac is 100 mass% within the said range. The number average molecular weight (GPC measurement, standard polystyrene conversion) of the resin is preferably 2,000 to 500,000. More preferably, it is 10,000-200,000. If the molecular weight is less than 2,000, the water resistance and weather resistance of the resin are inadequate, and on the other hand, if the molecular weight exceeds 500,000, the resin of the present invention is used as a paint. Inferior paintability.

  As said compound a, compounds, such as a sulfonic acid type, a carboxylic acid type, a phosphoric acid type, and an amine type, can be used. The compound a has an effect of improving the adhesive strength to the base material, microporous layer or adhesive layer of the film made of the resin of the present invention, and imparts water dispersion and self-emulsification to the resin of the present invention.

Examples of the sulfonic acid compound a include the following compounds and derivatives thereof.

  Further, as the carboxylic acid-based compound a, dimethylolpropanoic acid, dimethylolbutanoic acid and their alkylene oxide low-mole adducts (number average molecular weight less than 500), and γ-caprolactone low-mole adducts of these compounds (several numbers) (Average molecular weight less than 500), half esters derived from acid anhydride and glycerin, compounds derived from free radical reaction of monomers containing hydroxyl and unsaturated groups and monomers containing carboxyl and unsaturated groups, etc. Is mentioned. Particularly preferred compounds a are dimethylolpropanoic acid and dimethylolbutanoic acid (used as urethane resin in an acid value range of 5 to 40 mgKOH / g), N, N-bis (2-hydroxyethyl) -2-aminoethane. Sulfonic acid.

  The above are examples of the preferred compound a used in the present invention, and the present invention is not limited to these exemplified compounds. Accordingly, not only the exemplified compounds described above but also any other compound a that is currently commercially available and can be easily obtained from the market can be used in the present invention.

  When the resin of the present invention containing the segment of the compound a is used for emulsification of the resin in use, when the segment of the compound a is anionic (sulfonic acid, carboxylic acid, etc.), for example, organic Amines (ammonia, ethylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyldiethanolamine, N-phenyldiethanolamine, monoethanolamine, dimethylethanolamine, diethylethanolamine, morpholine, N-methylmorpholine , 2-amino-2-ethyl-1-propanol, etc.), alkali metals (lithium, potassium, sodium, etc.), inorganic alkalis (lithium hydroxide, sodium hydroxide, potassium hydroxide, etc.), etc. It is, and when the segments of the compound a is cationic (tertiary amine) is an organic acid, for example, be neutralized formic acid, lactic acid, and the like acetic acid.

  The compound b is contained as a polysiloxane segment in the resin of the present invention, and the polysiloxane segment is contained in the main chain of the resin or in a branched state. That is, if the compound b as a raw material is reactive at both ends, the segment of the compound b is from the backbone of the resin main chain, and if the compound b is single-ended or branched reaction type, from the resin main chain. It will be contained in a branched state.

  Examples of the compound b used in the present invention include the following compounds. This includes an epoxy-modified polysiloxane modified using an active hydrogen-containing group, but is included because it reacts with an isocyanate group and is contained in a polyurethane resin.

(1) Amino-modified polysiloxane

(2) Epoxy-modified polysiloxane

  The above epoxy compound can be used by reacting with a polyol, polyamide, polycarboxylic acid or the like to have a terminal active hydrogen-containing group.

(3) Alcohol-modified polysiloxane

(4) Mercapto-modified polysiloxane

  Compound b listed above is a preferred compound used in the present invention, but the present invention is not limited to these exemplified compounds. Therefore, not only the compounds exemplified above, but also any other compounds that are currently commercially available and can be easily obtained from the market can be used in the present invention. Particularly preferred compound b in the present invention is a polysiloxane having two hydroxyl groups or amino groups.

  Besides these, polylactone (polyester) -polysiloxane obtained by modifying polysiloxane with lactone, polyalkylene oxide-polysiloxane modified with alkylene oxide, and the like are also preferably used. Preferred lactones used here are β-propiolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone, 7-heptanolide, 8-octanolide, γ-valerolactone, γ-caprolactone and δ-caprolactone. .

  Examples of the alkylene oxide include ethylene oxide, propylene oxide, α-butylene oxide, β-butylene oxide, hexene oxide, cyclohexene oxide, styrene oxide, α-methylstyrene oxide, and the like.

  The polyol as the compound c is preferably a conventionally known one such as a short chain diol, a polyhydric alcohol and a polymer polyol conventionally used for polyurethane production, and a polyamine is conventionally used for polyurethane production. The short chain diamine etc. currently used can be used. These are not particularly limited. Each compound used below is described.

  Examples of the short-chain diol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 1,6-hexamethylene glycol, and neopentyl. Aliphatic glycols such as glycols and alkylene oxide low-mole adducts thereof (number average molecular weight less than 500), alicyclic glycols such as 1,4-bishydroxymethylcyclohexane and 2-methyl-1,1-cyclohexanedimethanol And its alkylene oxide low molar adduct (number average molecular weight less than 500), aromatic glycols such as xylylene glycol and its alkylene oxide low molar adduct (less than number average molecular weight 500), bisphenol A, thiobisphenol and Bisphenols and alkylene oxide low molar adducts of such fine sulfone bisphenol (number average molecular weight of less than 500), and compounds such as alkyl dialkanolamines, such as alkyl diethanolamine of C1~C18 thereof.

  Examples of the polyhydric alcohol compound include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, tris- (2-hydroxyethyl) isocyanurate, 1,1,1-trimethylolethane, and 1,1, Examples thereof include 1-trimethylolpropane. These can be used alone or in combination of two or more.

Examples of the polymer polyol include the following.
(1) Polyether polyols such as those obtained by polymerizing or copolymerizing alkylene oxides (ethylene oxide, propylene oxide, butylene oxide, etc.) and / or heterocyclic ethers (tetrahydrofuran, etc.) are specifically exemplified. Are polyethylene glycol, polypropylene glycol, polyethylene glycol-polytetramethylene glycol (block or random), polytetramethylene ether glycol and polyhexamethylene glycol,

(2) Polyester polyols such as aliphatic dicarboxylic acids (eg succinic acid, adipic acid, sebacic acid, glutaric acid and azelaic acid) and / or aromatic dicarboxylic acids (eg phthalic anhydride, isophthalic acid and Terephthalic acid, etc.) and low molecular weight glycols (eg, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 1,6-hexamethylene glycol) , Neopentyl glycol and 1,4-bishydroxymethylcyclohexane) are exemplified. Specifically, polyethylene adipate diol, polybutylene adipate diol, polyhexamethylene adipate diol, polyneopenty Adipate diol, polyethylene / butylene adipate diol, polyneopentyl / hexyl adipate diol, poly-3-methylpentane adipate diol, and polybutylene isophthalate diol, etc.,

(3) Polylactone polyols such as polycaprolactone diol and poly-3-methylvalerolactone diol,
(4) Polycarbonate diol, such as polyhexamethylene carbonate diol, 1,6-, 1,5-, or 1,4-modified polycarbonate diol,
(5) Polyolefin polyol, such as polybutadiene glycol and polyisoprene glycol, or a hydride thereof,
(6) Polymethacrylate diols such as α, ω-polymethylmethacrylate diol and α, ω-polybutylmethacrylate diol are exemplified.

  The structure and molecular weight of these polyols are not particularly limited, but usually the number average molecular weight is preferably about 500 to 4,000, and these polyols can be used alone or in combination of two or more.

  Preferred polyamines as the polyamine include, for example, short chain diamines, aliphatic, aromatic diamines, long chain diamines and hydrazines. Examples of the short-chain diamine include aliphatic diamine compounds such as ethylenediamine, trimethylenediamine, hexamethylenediamine, trimethylhexamethylenediamine and octamethylenediamine, phenylenediamine, and 3,3′-dichloro-4,4′-diaminodiphenylmethane. Aromatic diamine compounds such as 4,4′-methylenebis (phenylamine), 4,4′-diaminodiphenyl ether and 4,4′-diaminodiphenylsulfone, cyclopentanediamine, cyclohexyldiamine, 4,4-diaminodicyclohexylmethane, Examples include alicyclic diamine compounds such as 1,4-diaminocyclohexane and isophoronediamine.

Examples of the long-chain diamine include those obtained by polymerizing or copolymerizing alkylene oxides (ethylene oxide, propylene oxide, butylene oxide, etc.), and specific examples include polyoxyethylene diamine and polyoxypropylene diamine. Further, hydrazines such as hydrazine, carbodihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide and phthalic acid dihydrazide can be mentioned.
If an amino-modified silane coupling agent is used, a self-curing reaction type paint can be designed. For example, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyl Examples include methyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, and 3-ureidopropyltriethoxysilane. These can be used alone or in combination of two or more. As the polyol and polyamine, polyether-based diol compounds and diamine compounds such as ethylene oxide and propylene oxide are preferable.

  As the compound d, any of those conventionally used for producing polyurethane can be used and is not particularly limited. Preferred examples of the polyisocyanate compound include toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, 4-methoxy-1,3-phenylene diisocyanate, 4-isopropyl-1,3-phenylene diisocyanate, 4- Chlor-1,3-phenylene diisocyanate, 4-butoxy-1,3-phenylene diisocyanate, 2,4-diisocyanate diphenyl ether, 4,4′-methylenebis (phenylene isocyanate) (MDI), durylene diisocyanate, tolylene diisocyanate, xylylene Diisocyanate (XDI), 1,5-naphthalene diisocyanate, benzidine diisocyanate, o-nitrobenzidine diisocyanate, and 4,4'-diisocyanate dibenzyl Aromatic diisocyanates such as methylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, aliphatic diisocyanates such as trimethylhexamethylene diisocyanate and 1,10-decamethylene diisocyanate, 1,4-cyclohexylene diisocyanate 3,4'-methylenebis (cyclohexyl isocyanate), 1,5-tetrahydronaphthalene diisocyanate, isophorone diisocyanate, alicyclic diisocyanates such as hydrogenated MDI and hydrogenated XDI, etc. Propyltriethoxysilane, etc., or these diisocyanate compounds and low molecular weight polyols and polyamines are terminated with isocyanate Polyurethane prepolymers obtained by reacting such that it can be of course also be used.

  The production method of the resin of the present invention using the compounds a to d is not particularly limited, and a conventionally known polyurethane production method can be used. For example, in the presence or absence of an organic solvent that does not contain an active hydrogen-containing group in the molecule, the compound a, the compound b, the compound c, and the compound d may be chain-extended with a low molecular diol as necessary. It is usually used by the one-shot method or the multi-stage method in such a composition that the equivalent ratio of isocyanate group and active hydrogen-containing group is usually 1.0 or around (0.9 to 1.1). The reaction is carried out at 20 to 150 ° C., preferably 60 to 110 ° C. until the product reaches the theoretical NCO%, and the resulting resin is emulsified with water and a neutralizing agent, and then chain-extended with a low molecular diamine to generate isocyanate groups. The resin of the present invention (or its emulsion in water) can be obtained through a solvent removal step as necessary.

  In the present invention, a catalyst can be used as necessary in the urethane synthesis. For example, salts of metals and organic and inorganic acids such as dibutyltin laurate, dioctyltin laurate, stannous octoate, lead octylate, tetra-n-butyl titanate, and organic metal derivatives, organic amines such as triethylamine, diaza Bicycloundecene catalysts and the like can be mentioned.

  The resin of the present invention may be synthesized without a solvent, or may be synthesized using an organic solvent if necessary. Preferred solvents as organic solvents include those that are inert to isocyanate groups or less active than the reaction components. For example, ketone solvents (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), aromatic hydrocarbon solvents (toluene, xylene, swazol (aromatic hydrocarbon solvents manufactured by Cosmo Oil Co., Ltd.)), Solvesso (Exxon Chemical Co., Ltd.) Company-made aromatic hydrocarbon solvents), aliphatic hydrocarbon solvents (n-hexane, etc.), alcohol solvents (methyl alcohol, ethyl alcohol, isopropyl alcohol, etc.), ether solvents (dioxane, tetrahydrofuran, etc.) , Ester solvents (ethyl acetate, butyl acetate, isobutyl acetate, etc.), glycol ether ester solvents (ethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate, 3-methyl-3-methoxybutyl acetate) Over DOO, such as ethyl 3-ethoxypropionate), amide solvents (dimethylformamide, dimethyl acetamide), lactam solvent (N- methyl-2-pyrrolidone, etc.). Of these, methyl ethyl ketone, ethyl acetate, acetone, and tetrahydrofuran are preferable in consideration of solvent recovery, solubility during urethane synthesis, reactivity, boiling point, and emulsification dispersibility in water.

  In the present invention, in the resin synthesis step, when an isocyanate group remains at the polymer terminal, an isocyanate terminal termination reaction may be added. For example, not only monofunctional compounds such as monoalcohols and monoamines, but also compounds having two kinds of functional groups having different reactivities with respect to isocyanate can be used. Monoalcohols such as alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, tert-butyl alcohol; monoethylamine, n-propylamine, diethylamine, di-n-propylamine, di-n -Monoamines such as butylamine; alkanolamines such as monoethanolamine and diethanolamine, and the like. Among these, alkanolamines are preferable because of easy reaction control.

  In the production of the resin of the present invention, additives may be added as necessary. For example, antioxidants (hindered phenols, phosphites, thioethers, etc.), light stabilizers (hindered amines, etc.), UV absorbers (benzophenones, benzotriazoles, etc.), gas discoloration stabilizers (hydrazines, etc.) ), Metal deactivators and the like, and two or more of these.

  Next, as the aqueous crosslinking agent (2) used in the present invention, polyisocyanate crosslinking agents (including block type), melamine crosslinking agents, carbodiimide crosslinking agents, oxazoline crosslinking agents, epoxy crosslinking agents, silanols. Examples thereof include a system crosslinking agent, an inorganic crosslinking agent, a radical polymerization crosslinking agent ((meth) acryloyl group-containing crosslinking agent), and a cationic polymerization crosslinking agent (epoxy, oxetane, vinyl ether crosslinking agent). In particular, in the present invention, a crosslinking method utilizing the reactivity of a hydrophilic group such as a urethane group and / or a carboxyl group is preferable, but is not particularly limited.

  Examples of the crosslinking method using a urethane group include crosslinking with a polyisocyanate crosslinking agent, but the polyisocyanate crosslinking agent is not particularly limited, and any conventionally known one can be used. For example, water-dispersed polyfunctional aromatic isocyanates, water-dispersed polyfunctional aliphatic isocyanates, water-dispersed fatty acid-modified polyfunctional aliphatic isocyanates, water-dispersed blocked polyfunctional aliphatic isocyanates and other block-type polyisocyanates, water-dispersed Type polyisocyanate prepolymer. These polyisocyanate cross-linking agents are effective in improving the adhesion between the coating film and the base sheet if they are in an appropriate amount, but if the amount used is too large, unreacted isocyanate remains and becomes a problem. It is 120 mass parts or less with respect to 100 mass parts of resin, Preferably it exists in the range of 1-50 mass parts.

  Conventional crosslinking methods using hydrophilic groups such as carboxyl groups include epoxy crosslinking agents, carbodiimide crosslinking agents, oxazoline crosslinking agents, oxetane crosslinking agents, vinyl ether crosslinking agents, and metal complex crosslinking agents. The well-known thing used can be used and it does not specifically limit. For example, as an epoxy-type crosslinking agent, conventionally well-known commercially available epoxy resins, such as "Epicoat" (made by Yuka Shell Epoxy), are mentioned. As the carbodiimide-based cross-linking agent, a commercially available product under the trade name “Carbodilite” (manufactured by Nisshinbo) can be used. The crosslinking agent reacts with a carbodiimide group and a carboxyl group to form N-acyl urea, thereby improving the coating film performance. Moreover, in the silanol type crosslinking agent (silyl type crosslinking agent), the coating film performance is improved by self-condensation.

  In particular, in the present invention, the use of an oxazoline-based cross-linking agent causes a slow reaction in the low temperature region (80 to 100 ° C.) during drying of the paint, while the reaction is completed in the high temperature region during heat treatment. Is preferable because it is possible. As the oxazoline-based crosslinking agent, commercially available products such as “Epocross” trade name (manufactured by Nippon Shokubai Co., Ltd.), WS-300, WS-500, WS-700, WS-R10 and the like can be obtained and used. These crosslinking agents take a crosslinked structure by reacting the oxazoline group of the crosslinking agent and the carboxyl group of the resin to form an amide ester. As the oxazoline-based crosslinking agent, those having a Tg of −5 to 90 ° C. and an oxazoline group equivalent of about 100 to 400 can be used. Particularly preferred is Tg = −5 to 25 ° C. (room temperature or lower), and an oxazoline group equivalent of 200-350. When Tg is lower than the above range, there is a concern about blocking, whereas when Tg is higher than the above range, cracks occur in the film. Also, if the oxazoline group equivalent is lower than the above range, the effect of the intended performance will not be manifested unless the addition amount of the crosslinking agent is increased, while if the oxazoline group equivalent is higher than the above range, the oxazoline group is adjacent. As a result, the reactivity decreases and an unreacted oxazoline group remains. These oxazoline-based crosslinking agents are within a range of 0.1 to 50 parts by mass, preferably 1 to 40 parts by mass with respect to 100 parts by mass of the resin of the present invention. If the amount of the crosslinking agent used is lower than the above range, the effect of the crosslinking agent cannot be obtained. On the other hand, if the amount of the crosslinking agent used is higher than the above range, occurrence of blocking, reduction in film formability and cost increase Become.

  As the metal complex-based crosslinking agent, titanium organic compound-based, zirconium organic compound-based commercially available under the trade name of “Orgatyx” (manufactured by Matsumoto Pharmaceutical Co., Ltd.) are available, and aluminum, chromium, cobalt, copper, Iron, nickel, vanadium, zinc, indium, calcium, magnesium, manganese, yttrium, cerium, strontium, palladium, barium, molybdenium, lanthanum, tin sold under the trade name "Narsem" (manufactured by Nippon Kagaku Sangyo Co., Ltd.) An acetylacetone complex can be obtained and used. As the oxetane-based cross-linking agent, a commercial product of “ETANACOL” under the trade name (manufactured by Ube Industries) can be obtained and used. As the vinyl ether-based crosslinking agent, commercially available products such as BASF, IPS Japan, Maruzen Petrochemical, Nippon Shokubai, etc. can be obtained and used. The crosslinking agent reacts by cationic polymerization or forms an alkoxyester by Michael addition reaction.

  Moreover, as a silane coupling crosslinking agent, it is marketed by the brand name (made by Shin-Etsu Chemical Co., Ltd.) of "KBM-, KBE-series". These crosslinking agents are particularly effective for improving the durability if they are in an appropriate amount. However, if the amount used is too large, the pot life is shortened and the film becomes brittle. 40 parts by mass or less, preferably 0.5 to 20 parts by mass.

  Moreover, the vinyl ether type crosslinking agent which is a cationic polymerization type crosslinking agent can react with a urethane group or a carboxyl group. Of course, it can be cured by irradiation with an electron beam.

  The paint of the present invention may be prepared without a solvent, but is preferably dissolved or dispersed in an aqueous medium, more preferably by adding the resin of the present invention and the aqueous cross-linking agent in ion-exchanged water. can get. The content of the component in the solid content of the paint is 10 to 80% by mass of the resin of the present invention, more preferably 20 to 70% by mass, and 0.1 to 50% by mass of the aqueous crosslinking agent, preferably 1. -40 mass%. In addition, although the solid content of the prepared coating material is not specifically limited, Usually, it is about 5-100 mass%.

  The essential components of the paint of the present invention are as described above. However, as long as the object of the present invention is not hindered, conventionally known resins and various additives such as antioxidants (hindered phenols, phosphites) , Thioethers, etc.), light stabilizers (hindered amines, etc.), UV absorbers (benzophenones, benzotriazoles, etc.), gas discoloration stabilizers (hydrazines, etc.), metal deactivators, etc. Is mentioned. Furthermore, designability imparting agents (organic fine particles, inorganic fine particles), antifungal agents, flame retardants and other additives can be used as appropriate. Examples of the organic fine particles and inorganic fine particles may include silica, silicone resin fine particles, fluororesin fine particles, acrylic resin fine particles, urethane resin fine particles, silicone-modified urethane resin fine particles, polyethylene fine particles, and reactive siloxane.

  The method for producing the synthetic artificial leather of the present invention may be a conventionally known method, and the production method itself is not particularly limited. For example, (1) A high molecular weight type urethane resin solution synthesized in an organic solvent mainly composed of N, N-dimethylformamide (DMF) is applied on a base sheet, and the coating layer is solidified in water. After forming and drying a microporous layer having a thickness of 200 to 2,000 μm, the coating material of the present invention was directly coated on the microporous layer with a coating machine such as a gravure and dried to a thickness of 100 A method of forming a skin layer (silver surface layer) of ˜1,500 μm (a system in which DMF is finally recovered), (2) The coating composition of the present invention is applied on release paper and dried. Apply a water-based urethane adhesive, an adhesive made of 100% solid of urethane resin or ester resin (including reactive type) on a 20-100 μm thick film, or wet laminate or Performing transfer forming surface to form a skin layer in accordance with the line lamination conditions.

  As the synthetic artificial leather substrate used in the present invention, any conventionally known synthetic artificial leather substrate can be used. For example, a cotton fabric made of twill weave, plain weave, etc. Examples include blankets, rayon cloths, nylon cloths, polyester cloths, Kevlar cloths, non-woven fabrics (polyesters, nylons, various latexes), various films and sheets.

  A preferable material for forming the adhesive layer is a water-based urethane adhesive (e), a solventless urethane adhesive (including a reactive type) (f), or a reaction between a low molecular polyol and a dibasic acid. Examples thereof include solvent-free ester adhesives (including reactive types) (g).

  Examples of the water-based urethane adhesive (e) include a self-curing urethane adhesive having a water-soluble group, a hydroxyl group, and a blocked isocyanate group, and a self-curing urethane adhesive having a silanol group or an unsaturated group. Examples of the solventless urethane adhesive include hot-melt urethane adhesive, self-curing urethane adhesive having an isocyanate group, a blocked isocyanate group, a silanol group, or an unsaturated group.

  The self-curing urethane-based adhesive used above comprises a polyisocyanate, a polyol and / or a polyamine, and a compound having at least one amino group and at least one hydroxyl group in the same molecule (if necessary). It is obtained by reacting with a chain extender so that free isocyanate groups remain, and blocking the remaining free isocyanate groups. Examples of the compound having at least one amino group and at least one hydroxyl group in the same molecule include 2- (hydroxymethylamino) ethanol, aminopropanol, aminobutanol, 4-methylaminobutanol, and 2-hydroxyethyl. Aminopropanol, diethanolaminopropylamine, 1-aminopropanediol, 1- (methylamino) propanediol, N-methyldiethanolamine, N-methylethanolamine, N-ethylethanolamine, Nn-butylethanolamine, N- Aliphatic aminoalcohols such as t-butylethanolamine and N- (β-aminoethyl) isopropanolamine, hydroxyethylpiperas such as 3-piperazinemethanol, 2-piperazineethanol and 4-piperazinol Compounds such emission systems. These can be used alone or in combination of two or more.

  The blocking agent for the isocyanate group of the self-curing urethane adhesive is not particularly limited, and one or more known ones can be used. As the blocking agent, for example, oxime, alcohol, phenol, active methylene, lactam, acid amide, acid imide and the like can be used. Examples of the blocking agent include oxime compounds (formal oxime, acetoald oxime, acetone oxime, methyl ethyl ketoxime, methyl isobutyl ketoxime, cyclohexanone oxime, etc.), alcohol compounds (2-hydroxypyridine, butyl cellosolve, propylene glycol monomethyl ether). , Ethylene glycol, benzyl alcohol, methanol, ethanol, n-butanol, isobutanol, 2-ethylhexanol, etc.), phenolic compounds (phenol, cresol, ethylphenol, butylphenol, etc.), active methylene compounds (dimethyl malonate, malonate) Diethyl acetate, methyl acetoacetate, ethyl acetoacetate, acetylacetone, etc.), lactam compounds (ε-caprolactam) δ- valerolactam and γ- butyrolactam), acid amide-based compound (acid amide, etc.), acid imide compounds (such as maleic acid Imi) and the like.

  The silane coupling agent used for the synthesis of the silanol group-containing urethane-based adhesive is not particularly limited, and one or more of known silane coupling agents can be used. For example, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane Examples include ethoxysilane, 3-aminopropyltrimethoxysilane, and 3-aminopropyltriethoxysilane.

  In the unsaturated group-containing urethane-based adhesive (ultraviolet ray curing, electron beam curing), the method for introducing an unsaturated group into the same molecule is not particularly limited, and one or more of known ones should be used. Can do. For example, after synthesizing a terminal isocyanate prepolymer, there is a technique of reacting a compound containing a hydroxyl group and a vinyl group in the same molecule. Examples of the compound having a hydroxyl group and a vinyl group in the same molecule include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, glycerin monoallyl ether, Examples include trimethylolpropane diallyl ether and pentaerythritol triallyl ether.

  Examples of the reactive diluent that is diluted during and / or after the reaction include radical polymerization monofunctional acrylate compounds, polyfunctional acrylate compounds, and cationic polymerization compounds in addition to the above-mentioned compounds. Examples of radical polymerization type monofunctional acrylate compounds include tetrahydrofurfuryl (meth) acrylate, 2-ethylhexyl (meth) acrylate, methoxyethyl (meth) acrylate, N-vinylpyrrolidone, phenyl (meth) acrylate, 2 -Hydroxyethyl (meth) acrylate, diethylene glycol di (meth) acrylate, N, N-dimethylacrylamide, N-isopropylacrylamide, acryloylmorpholine and the like. Examples of polyfunctional acrylate compounds include trimethylolpropane tri (meth) acrylate, pentaerythritol hexa (meth) acrylate, trimethylolpropane di (meth) acrylate, pentatrithritol tetra (meth) acrylate, and the like. . Examples of the cationic polymerization diluent include an epoxy compound, an oktacene compound, and a vinyl ether compound.

  When the unsaturated group-containing urethane adhesive is used, a photopolymerization initiator is used. Those which generate radicals by light and the radicals react with the polymerizable unsaturated compound are desirable. Although not particularly limited, for example, benzophenone, acetophenone, benzoin, benzoin isobutyl ether, benzoin isopropyl ether, benzoin ethyl ether, 2,4-dimethylthioxanthone, 2-chlorothioxanthone, ethylanthraquinone, 4,4′-bisdimethyl Examples include aminobenzophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, and benzylmethylketanol. Examples of the cationic polymerization initiator include diazonium salt type compounds, sulfonium salt type compounds, iodonium salt type compounds, and the like. These compounds may be used in combination. In the case of electron beam irradiation, it is not necessary to use a photopolymerization initiator.

  The solventless polyester-based adhesive is not particularly limited, and one or more kinds of known ones can be used. For example, in the case of a low molecular polyol, ethylene glycol, propanediol, butanediol, pentanediol, hexanediol, neopentylglycol, etc., dibasic acids are adipic acid, sebacic acid, dodecanedioic acid, phthalic acid, isophthalic acid, Those obtained by a known condensation reaction from terephthalic acid can be used.

  Hereinafter, the present invention will be described more specifically with reference to production examples, examples and comparative examples, but the present invention is not limited thereto. Moreover, in the following sentence, “part” indicates mass part, and “%” indicates mass%.

[Synthesis Examples 1 to 3]
The synthesis examples 1-3 of the urethane type resin used for this invention are shown.
After replacing the reaction vessel equipped with a stirrer, reflux condenser, thermometer, nitrogen blowing tube and manhole with nitrogen gas, hydrophilic group-containing compound (compound a), polymer diol (compound c), chain extender (short) A predetermined amount of chain diol component: Compound E), polysiloxane having a hydroxyl group at both ends or one end (Compound b) and acetone were added and dissolved uniformly to adjust the solution concentration. Subsequently, hexamethylene diisocyanate (compound d) was added at an equivalent ratio of a predetermined amount (NCO / OH = 2.0) and reacted at 80 ° C, reacted until the theoretical NCO% was reached, cooled to 50 ° C, Add ion exchange water with a solid content of 30% or 20% and a neutralizing agent in a predetermined amount (amount equivalent to COOH), uniformly emulsify the system, and an ethylenediamine component (amount equivalent to the remaining NCO%) ) To extend the chain. Finally, the acetone in the system was recovered by vacuum degassing to obtain three types of urethane resins used in the present invention. Table 1 shows the raw material composition of the urethane resin.

註)
Compound a:
A-1: dimethylolbutanoic acid a-2: dimethylolpropanoic acid

Compound c:
PCD: Plaxel CD220, polycarbonate diol (Daicel Chemical Industries, average molecular weight 2,000)

Chain extender E:
・ 1,3BD: 1,3-butanediol

Compound b:
B-1: (both terminal polysiloxane diol, n is an integer, average molecular weight 1,900)

B-2: (one-end polysiloxane diol, n is an integer, average molecular weight 3,000)

TEA: triethylamine HDI: hexamethylene diisocyanate EDA: ethylenediamine

[Synthesis Example 4: Synthesis of Urethane Resin for Microporous Layer]
After replacing the reaction vessel equipped with a stirrer, reflux condenser, thermometer, nitrogen blowing tube and manhole with nitrogen gas, carbonate diol (hydroxyl value = 56) 150 parts, ethylene glycol 10 parts and 1,4-butylene glycol 10 The part was dissolved in a predetermined amount of N, N-dimethylformamide (DMF) to adjust the solution concentration. Subsequently, 4,4′-methylenebis (phenylene isocyanate) (MDI) was added in a predetermined amount (NCO / OH = 1.0) and reacted at 80 ° C. until the NCO% disappeared in the IR spectrum. In the high molecular weight urethane resin (A-1) for the microporous layer, the resin solution had a nonvolatile content of 30% and a viscosity of 1,200 dPa · s.

[Synthesis Example 5: Synthesis of water-based urethane adhesive]
A reaction vessel equipped with a stirrer, reflux condenser, thermometer, nitrogen blowing tube and manhole was replaced with nitrogen gas, and then 10.72 parts of dimethylolpropionic acid as a hydrophilic group-containing compound and a number average molecular weight of 1000 as a polymer diol. 100.0 parts of polyhexamethylene carbonate diol, 1.80 parts of 1,3-butylene glycol and 108.6 parts of acetone were added as a chain extender (short chain diol). Subsequently, 50.4 parts of hexamethylene diisocyanate was added as a polyisocyanate, and dibutyltin dilaurate was added as a catalyst at 80 ° C. until the NCO% of the resin reached the theoretical value.

Next, 3.48 parts of methyl ethyl ketoxime was added as a blocking agent, and the reaction was continued at 80 ° C. until the NCO% of the resin reached the theoretical amount. The obtained reaction product is cooled to 50 ° C., 60.7 parts of ion-exchanged water having a solid content of 40%, and 8.10 parts of triethylamine as a neutralizing agent are added in a predetermined amount, and the inside of the system is evenly mixed under stirring conditions. It was emulsified until. In the obtained urethane water dispersion, 3.00 parts of aminopropanol as a compound in which at least one amino group and at least one hydroxyl group coexist and 9.85 parts of isophoronediamine as a polyamine are diluted with an equal amount of water. In addition, it was reacted with the NCO group of the urethane water dispersion. The reaction was carried out until the absorption due to the free isocyanate group at 2,270 cm ⁻¹ disappeared in the infrared absorption spectrum. Finally, acetone in the system was recovered by vacuum degassing.

  The obtained self-curing water-based urethane adhesive had a solid content of 40.3%, an acid value of 25 mgKOH / g, a hydroxyl value of 13 mgKOH / g, and an average particle size of 20 nm. This water-based urethane adhesive is designated as B-1.

[Synthesis Example 6: Synthesis of water-based urethane adhesive]
A reaction vessel equipped with a stirrer, reflux condenser, thermometer, nitrogen blowing tube and manhole was replaced with nitrogen gas, and then 10.72 parts of dimethylolpropionic acid as a hydrophilic group-containing compound and a number average molecular weight of 1000 as a polymer diol. 100.0 parts of polyhexamethylene carbonate diol, 1.80 parts of 1,3-butylene glycol and 108.6 parts of acetone were added as a chain extender (short chain diol). Subsequently, 50.4 parts of hexamethylene diisocyanate was added as a polyisocyanate, and dibutyltin dilaurate was added as a catalyst at 80 ° C. until the NCO% of the resin reached the theoretical value.

The obtained reaction product is cooled to 50 ° C., and a predetermined amount of ion-exchanged water having a solid content of 40% and 8.10 parts of triethylamine as a neutralizing agent are added, and the mixture is emulsified under stirring conditions until uniform. I let you. To the obtained urethane water dispersion, 17 parts of N-2- (aminoethyl) -3-aminopropyltrimethoxysilane and 9 parts of isophoronediamine as a polyamine were added, and the reaction was 2,270 cm ^{−1 in} the infrared absorption spectrum. This was performed until absorption due to free isocyanate groups disappeared. Finally, acetone in the system was recovered by vacuum degassing. This water-based urethane adhesive is designated as B-2.

[Synthesis Example 7: Synthesis of UV-curable adhesive]
After replacing the reactor equipped with a stirrer, reflux condenser, thermometer, nitrogen blowing tube and manhole with nitrogen gas, 100.0 parts of polyhexamethylene carbonate diol having a number average molecular weight of 2000, hydroxyl group and vinyl group are the same molecule 6.6 parts of glycerin monoallyl ether as a compound contained therein, 52 parts of N, N-dimethylacrylamide as a diluent are charged, and when heated to 60 ° C. and uniform, 15 parts of hexamethylene diisocyanate is added as polyisocyanate. After adding dibutyltin dilaurate as a catalyst at 80 ° C. and confirming that there is no absorption due to a free isocyanate group of 2,270 cm ^{−1 in} the infrared absorption spectrum, it is cooled to 50 ° C., and Irgacure which is a photoinitiator. 5 parts of 651 were added. Let the obtained ultraviolet curable urethane type adhesive be B-3.

[Synthesis Example 8: Synthesis of urethane-modified reactive ester adhesive]
A reaction vessel equipped with a stirrer, reflux condenser, thermometer, nitrogen blowing tube and manhole was replaced with nitrogen gas, and then 20 parts of adipic acid, 30 parts of terephthalic acid and 53 parts of 1,6-hexanediol were charged up to 210 ° C. The temperature was raised. The reaction was carried out for 3 hours after reaching 200 ° C. After cooling to 100 ° C., a predetermined amount (NCO / OH = 2.0) of isophorone diisocyanate was added, and the reaction was further carried out for 3 hours. The obtained reactive urethane-modified ester adhesive had a non-volatile content of 100% and a melting point of 93 ° C. This urethane-modified reactive ester adhesive is designated as B-4.

Example 2, Reference Examples 1 , 3 and Comparative Example 1
The components described in Table 1 below were blended to prepare paints of the present invention (Examples), reference examples and comparative examples. The solid content of these paints was adjusted to 20% by adjusting the amount of ion-exchanged water.

Synthesis Example 1: Non-siloxane modified urethane resin C-1: Carbodilite V-02 (Nisshinbo Co., Ltd., carbodiimide-based crosslinking agent)
C-2: Epocross WS-500 (Nippon Shokubai Co., Ltd., oxazoline-based crosslinking agent)
C-3: WB40-100 (Asahi Kasei Chemicals, water-dispersed isocyanate)
Colorant: Seika Seven DW-794 Black (manufactured by Dainichi Seika Kogyo Co., Ltd., water dispersion type colorant)

Reference example 4
On the dough, 1,000 g / m ² · wet of a compounded solution obtained by diluting 100 parts of urethane-based resin for microporous layer (Synthesis Example 4) with 100 parts of DMF was applied in a coagulation tank (DMF / water = 5/95). After solidifying for 10 minutes, passing through water washing / mangle and removing the DMF process 5 times, drying at 130 ° C. for 10 minutes to finish the microporous layer, and coating example 1 is applied in an amount of 40 μm. The synthetic artificial leather was produced by drying at 3 ° C. for 3 minutes.

Example 5
On the release paper (EV130 TPD-R8, manufactured by Lintec), the above paint example 2 was applied (20 μm · Dry amount) and dried (120 ° C., 3 minutes dried), and then the adhesive (B-1) was applied. After application (amount to be 40 μm · Dry) and drying (120 ° C., 3 minutes drying), the applied material and the fabric were pasted together with a laminator and aged at 40 ° C. for 2 days to produce a synthetic artificial leather.

Reference Example 6
On the release paper (EV130 TPD-R8, manufactured by Lintec), the paint example 3 was applied (20 μm · Dry amount) and dried (120 ° C., 3 minutes dried), and the adhesive (B-2) was applied. Application (amount to be 40 μm · Dry) and the applied material and the fabric were pasted together with a laminator, followed by heat treatment (140 ° C., 5 minutes drying), and the release paper was peeled off to produce a synthetic artificial leather.

Reference Example 7
On the release paper (EV130 TPD-R8, manufactured by Lintec), the coating example 1 was applied (20 μm · Dry amount) and after drying (120 ° C., 3 minutes drying), the adhesive (B-3) 100 After applying 5 parts of Epocros WS-500 (manufactured by Nippon Shokubai Co., Ltd., oxazoline-based cross-linking agent) to the part (amount to become 40 μm Dry), after applying ultraviolet ray 80 mJ / cm ² irradiation, Were laminated with a laminator, and the release paper was peeled off to produce a synthetic artificial leather.

Example 8
On the release paper (EV130 TPD-R8, manufactured by Lintec), the above paint example 2 was applied (20 μm · Dry amount) and dried (120 ° C., 3 minutes dried), and then heated to 100 ° C. in advance. After applying the adhesive (B-4) (40μm · Dry amount), the coated product and the fabric are pasted together with a laminator, aged for 2 days at 40 ° C, and the release paper is peeled off to lay the synthetic artificial leather. Produced.

Reference Example 9
After applying the above paint example 3 on a release paper (EV130 TPD-R8, manufactured by Lintec) (amount of 20 μm · Dry), 100 parts of the adhesive (B-3) is PHDI (HDI biuret type, product) Name: After applying 5 parts of Duranate 24A-100, manufactured by Asahi Kasei Chemicals Co., Ltd. (amount to be 40 μm · Dry), and after being irradiated with UV rays at 80 mJ / cm ² , the coated product and the fabric Lamination was carried out at 40 ° C. for 2 days, and the release paper was peeled off to produce a synthetic artificial leather.

Comparative Example 2
On the release paper (EV130 TPD-R8, manufactured by Lintec), the above paint example 4 is applied (20 μm · Dry amount) and dried (120 ° C., 3 minutes dried), and then heated to 100 ° C. in advance. After applying the adhesive (B-4) (40μm · Dry amount), the coated product and the fabric are pasted together with a laminator, aged for 2 days at 40 ° C, and the release paper is peeled off to lay the synthetic artificial leather. Produced.

上記実施例５、８、参考例４、６、７、９および比較例２で作製した合成擬革を下記の項目で評価して、評価結果を表４に示した。 The composition of the synthetic artificial leather produced in Examples 5 and 8, Reference Examples 4, 6, 7, and 9 and Comparative Example 2 is summarized in Table 3 below.

The synthetic artificial leather produced in Examples 5 and 8, Reference Examples 4, 6, 7, and 9 and Comparative Example 2 was evaluated according to the following items, and the evaluation results are shown in Table 4.

Here, the contents of each test item are shown.
<Measures against VOC>
○: When the solvent used is 0 Δ: Less than 5% ×: 5% or more

<Appearance>
○: Sensitive to look good, close to natural leather tone ×: Not so

<Texture>
○: Volumetric and soft △: Slightly hard ×: Hard

<Cold-resistant bending>
The test was conducted at 0 ° C. and 20,000 times of flexing with a flexo testing machine.
○: No change △: Some cracks ×: Severe cracks

<Abrasion test>
The number of wear until the appearance of the coated surface was changed with a No. 6 canvas and a load of 500 g was measured using a flat wear tester.
○: 2000 times or more Δ: 1000 to less than 2000 times ×: less than 1000 times

<Adhesion test>
A 180-degree peeling force was measured using HEIDON-14DR manufactured by Shinto Kagaku Co., Ltd., on the test piece in which the coated surfaces were bonded with an adhesive.
○: 1.2 kg / cm or more Δ: 0.8 kg / cm or more and less than 1.2 kg / cm ×: less than 0.8 kg / cm

<Hydrolysis resistance>
The adhesion strength with the substrate after the jungle test (temperature: 70 ° C., relative humidity 95%, 3 weeks) was measured and compared with the initial strength.
○: Retention rate is 70% or more △: 69-40%
×: Less than 40%

<Light resistance>
The adhesion strength with the base material after the sunshine weatherometer test (temperature: 63 ° C., no water, 120 hours) was measured and compared with the initial strength.
○: Retention rate is 70% or more △: 69-40%
×: Less than 40%

<Heat resistance>
The test was carried out in a gear oven, the temperature was 120 ° C., the adhesive strength with the substrate after 150 hours was measured, and compared with the initial strength.
○: Retention rate is 70% or more △: 69-40%
×: Less than 40%

  In the skin layer, the carbodiimide-based crosslinking agent and the water-dispersed isocyanate-based crosslinking agent tend to deteriorate due to light resistance and heat resistance of the ethylene oxide segment introduced for emulsification in water. In addition, the water-dispersed isocyanate-based crosslinking agent partially reacts with water during processing to deactivate the isocyanate group, resulting in slightly inferior durability.

  As described above, according to the present invention, the skin layer, which is an ecological material excellent in hydrolysis resistance, light resistance, heat resistance, texture, adhesive strength, cold bending resistance, and abrasion resistance, is a siloxane-modified urethane resin. Of an ester resin obtained by reacting an aqueous urethane adhesive or urethane adhesive (including reactive type) or a low molecular polyol with a dibasic acid. A highly durable synthetic artificial leather using an adhesive (including a reactive type) made of 100% solid is provided.

Claims (3)

A siloxane-modified urethane resin (1) and an aqueous crosslinking agent (2) are contained in an aqueous medium,
The siloxane-modified urethane resin (1) comprises a compound (a) having at least one active hydrogen-containing group and a hydrophilic group other than a hydroxyl group in the molecule, and a polysiloxane having at least one active hydrogen-containing group. (B), a resin obtained by reacting a polyol and / or polyamine (c) with a polyisocyanate (d),
The polyol and / or polyamine (c) is a polycarbonate diol,
The aqueous crosslinking agent (2) is an oxazoline crosslinking agent,
The compound (a) to (c) are used in an amount of 0.01 to 30% by mass of compound (a), 1 to 20% by mass of compound (b), and compounds (a) to (c). ) And the total amount of 100% by mass,
The compound (d) is used in such an amount that the total active hydrogen-containing group of the compounds (a) to (c) and the isocyanate group of the compound (d) are in an equivalent ratio (OH / NCO) of 0.9 to 1.1. A coating material for forming a skin layer of synthetic artificial leather, characterized in that The ratio of the polysiloxane segment in the siloxane-modified urethane resin (1) is 1 to 20 % by mass, and the number average molecular weight of the resin is 2,000 to 500,000. paint. The paint according to claim 1 or 2 , wherein the aqueous crosslinking agent (2) is an oxazoline crosslinking agent having a Tg of -5 to 90 (° C) and an oxazoline group equivalent of 100 to 400.